Background: Asthma is a non-communicable disease with high prevalence rate. The prevalence of uncontrolled asthma among asthma patients is linked to the presence of comorbidities, one of which is gastroesophageal reflux disease (GERD).The Asthma Control Test is a tools for assessing the degree of asthma control. The GerdQ questionnaire is a simple diagnostic tool for GERD. This study aims to determine the association between the incidence of GERD and the degree of asthma. Methods: This case-control analytical observational study analyzed asthma patients on controller treatment for one month at Wahidin Sudirohusodo Hospital and Hasanuddin University Hospital outpatient clinics. All respondents completed ACT and GerdQ. Results: A total of 100 asthma patients completed a questionnaire; it was found that 52% of the participants were female, with an average age of <40 years. Among the 75 asthma participants who had GERD, 61 (81.3%) experienced uncontrolled asthma. The odds ratio for the association was 9.25, with a p-value <0.0001. The study revealed a negative correlation between the GerdQ and ACT scores (R = 0.411). Conclusions: There was a significant association between GERD and the degree of asthma. Asthma patients with GERD were 9.25 times more likely to experience uncontrolled asthma.